1. Field of the Invention
The present invention relates to a semiconductor encapsulation adhesive composition, to a semiconductor encapsulation film-like adhesive, to a method for producing a semiconductor device and to a semiconductor device.
2. Related Background Art
Wire bonding systems employing metal small-gauge wires such as gold wires have been widely used in the past for connection of semiconductor chips and boards; however, as demands increase for reduced size, smaller thicknesses and higher functionality for semiconductor devices, it is becoming increasingly popular to employ flip-chip connection systems, wherein conductive protrusions known as “bumps” are formed on semiconductor chips and the electrodes of the board and semiconductor chips are directly connected through the bumps.
The methods used in flip-chip connection systems include metal bonding using solder or tin, metal bonding accomplished by application of ultrasonic vibration and formation of permanent mechanical contact by the contractive force of a resin, but metal bonding with solder or tin is most commonly employed because it results in more reliable joints.
Liquid crystal display modules, which continue to decrease in size and increase in functionality in recent years, employ semiconductor devices known as COF (Chip On Film) devices, wherein liquid crystal-driving semiconductor chips provided with gold bumps are mounted on a polyimide board bearing tin coated wirings by metal bonding via gold-tin eutectic connection.
Because gold-tin eutectic connection are formed in a COF, the joints must be at the eutectic temperature of 278° C. or above. Heating is carried out at above the eutectic temperature for a short connection time of no longer than 5 seconds, to improve productivity, and therefore the preset temperature of the apparatus must be a high temperature of 200-400° C.
In COF, it is necessary to underfill the gaps between the semiconductor chips and board with a resin in order to protect the joint from the external environment and avoid concentration of external stress on the joint, while also ensuring sufficient electronic insulation reliability for narrow-pitch interconnects. Current underfill methods generally involve injection of the liquid resin by capillary flow, and curing, after connection between the semiconductor chips and board, but the longer time required for injection between the reduced chip-board gaps formed in narrow-pitch connection tends to lower productivity. This problem can be surmounted by a method of connecting the chips and board after supplying an adhesive to the chips or board (see Japanese Unexamined Patent Publication No. 2006-188573 and Matsushita Denko Technical Report, vol. 54 No. 3, P53-58).